Determining location information using sampled data containing location-determining signals and noise

US6535163B1 · kind B1 · utility

Assignee

• Enuvis, Inc.

Inventors

• Anant Sahai · Rue de l'Église, US
• John Tsitsiklis · Lexington, US
• Benjamin Van Roy · San Mateo, US
• Andrew Chou · San Mateo, US
• Wallace Mann · Mill Valley, US
• Jesse Stone · Palo Alto, US
• Wungkum Fong · Oakland, US

Key dates

• Filing date: Jun 22, 2001
• Grant date: Mar 18, 2003
• Expiry date: Jun 22, 2021

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S19/30
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

To determine the location of a signal receiver, sampled data received from a receiver is divided into data segments of increasing length. Current ranges for a delay value and for a modulation frequency value are calculated relative to each satellite signal source that is overhead the signal receiver. Using the data segments of increasing length, the current ranges, estimates for the delay value and for the modulation frequency value are then iteratively calculated and updated. For each signal source, I and Q correlation integrals and their magnitude values are calculated using the modulation frequency value estimate and each of a range of delay values centered around the delay value estimate. The resulting magnitude-curve is interpolated using the calculated magnitude values. The location of the receiver is calculated using the shape of the magnitude-curve to represent the I and Q correlation integrals for each signal source.